Androgenic alopecia is the single largest type of recognizable alopecia to affect both men (50%) and women (30%), primarily of Caucasian origin. Androgenic alopecia or common baldness represents 99 percent of all cases of hair loss (Brodland and Muller, 1991). The condition is characterized by the gradual conversion of terminal hair to short, wispy, colorless vellus hair.
It is generally accepted that genetic hair loss arises from an inherited predisposition activated by circulating androgenic hormones. While many investigators have tried to isolate the causative androgen metabolite, no single molecule has emerged. For example, in comparative studies between non-balding controls, no significant difference between mean hormonal values or amounts has been detected. See Puolakka, 1980. This suggests that a sensitivity or receptivity to hormones at the cell binding sites within the dermal papilla is a possible factor. Several treatments are based on this theory using anti-androgens such as CPA (cyproterone acetate) in combination with ethinyl-estradiol and the aldosterone antagonist spironolactone, which, given in dosages from 75 to 100 mg per day has shown some benefit. See e.g., Rushton and Ramsay, 1992; Rushton et al. 1991.
Most treatment modalities currently employed (such as hair transplantation) have been performed based on the theory that some hair follicles are genetically predisposed for sensitivity to androgens in the body. However, transplantation methods can be painful and expensive, often resulting in an undesirable xe2x80x9cfakexe2x80x9d appearance. No single treatment modality has proven completely or repeatably successful in inducing, maintaining and/or increasing hair growth.
In 1980, the reversal of androgenic alopecia in a male patient receiving minoxidil for hypertension was revealed and minoxidil has since been used to promote hair growth, most commonly by topical application (Zapacosta, 1980). Minoxidil""s vasodilating effect on the scalp is one of the proposed mechanisms by which minoxidil promotes hair growth. However, despite its popularity, minoxidil has not performed in a completely satisfactory fashion in promoting hair growth in all target populations. While minoxidil has been shown to stimulate some hair growth at the apex region of the scalp, hair growth at the frontal region of the scalp, for the most part, has not been shown to be improved by minoxidil treatment alone.
Cosmetic treatment of age-related hair loss in androgenic alopecia patients with topical solutions of minoxidil (ROGAINE(copyright)) alone, or in combination with skin penetration enhancers, such as DMSO, has resulted in only moderate regrowth of hair in less than 40% of such patients (Katz, 1988). Moreover, treatments with topical solutions of minoxidil require multiple applications of the active ingredient each day, which can be very inconvenient as well as expensive.
There is a need for methods of treating hair loss that require fewer applications of active ingredient, e.g., minoxidil, and which will also provide hair regrowth sooner, in more abundance, and thicker, than is presently observed using minoxidil and known penetration enhancers. Further, there is a need for a hair loss treatment which can improve hair growth at the frontal as well as apex regions of the scalp.
The subject invention pertains to novel compositions and/or formulations containing minoxidil as an active ingredient in combination with other active agents and/or enhancer agents which increases the hair growth capability of the composition. Another aspect of the subject invention pertains to methods of using the novel compositions to treat male patterned baldness and to stimulate hair growth on the scalp, including both the apex and frontal regions of the scalp. In addition to, or in place of minoxidil, glycerol oxido esters and/or ketoconazole can be added to the subject hair growth compositions.
According to one aspect, the subject invention pertains to a topical composition designed for application to the scalp wherein said composition comprises, in admixture with a pharmaceutically acceptable carrier and minoxidil, one or more of the following components: saw palmetto extract; nettle root extract; Capsaicin; Niacin; Gingko Biloba; horsetail extract; phospolipid; glycero oxido esters; ursolic acid; ketoconazole; 1,4:3,6 dianhydro-2.5-di-o-methyl-D-glucitol; cycoldextrin; peppermint oil; or milk thistle. A particular aspect of the subject invention pertains to a composition for treating androgenic alopecia comprising minoxidil in combination with saw palmetto extract. A further aspect of the subject invention preferably comprises, in addition to the minoxidil and saw palmetto extract, a nettle root extract.
The subject compositions and methods provide a safe and effective way to increase hair growth of the scalp. These and other advantageous aspects of the subject invention are described in further detail below.